Apparatus for effecting a repeated closing of automatic switches



April 2, 1929. sc l 1,707,236

APPARATUS FOR EFFECTING A REPEATED CLOSING OF AUTOMATIC SWITCHES Filed Aug. 7, 1922 WET if L 7 {Win Patented Apr. 2, 1929.

UNITED STATES PATENT OFFICE.

FRITZ SCKHIDLIN, OF BADEH, SWITZERLAND, ASSIGNOB T AKTIENGESELLSCHAFT BROWN, BOVEBI & cm, OF BADEN, SWITZERLAND.

BPABATUB FOE EFFECTING A. BEIPEATED CLOSING .01 AUTOKATIC SWITCHES.

Application fled. August 7, 1922, Serial No. 580,284, and in Switzerland September 10, 1881.

This invention has for its object to provide improved automatic switches for electrical plants so designed that after they have been opened by the elfect of a disturbance, they 5 will close again in a short time, and if they do not remain closed as a consequence of the continuance of the disturbance, they will open again, and so on, until on the disturbancc continuing to operate, they will remain 0 on.

This cycle 0 o erations has been periormed previously y com licated switching apparatus, the complex c aracter of some 0 the parts of which involves a reduction of the degree of safety in working. In the device according to the resent invention the same result is obtaine in an inexpensive manner by the combination of well-known sin iplle devices.

e improved apparatus of this invention comprises as an essential feature a delayed action relay arran ed to control the automatic device for c using the switch and to prevent any further automatic closing of the 2 switch after the latter has been closed again n-times without result.

This is efiected according to this invention by setting the time-mechanism of this delayed-action relay for a period comprised between an amount equal to 'n-tlmes and (n1 1)-times the period required for each automatic closure of the switch.

The manner of operation of the improved apparatus will now be more fully described 85 with reference to the accompanying draw iug which illustrates diagrammatically b y way of example a simple embodiment 0 this invention. a

In the improved apparatus according to 0) this invention it is arranged that the switch shall not close again after it has been closed automatically three times in immediate shecemion and it has immediatelyopened a in.

When the supply of circuit a which eeds the mainswitch of the consuming network 0 is under volta e, the contact relay (I is closed, and there y the connecting leads for the two delayed action relays f and g (of which f may for exam is be set for ten secends, and for thirtyve seconds) are connected to t e voltage of an auxiliary source of current It.

If the switch I; is o n, the auxiliary contacts i and k are close Since the relay 0! is closed, the delayed action relays are energized. The relay then closes its contact after ten seconds, whereby the switching-in magnet m is caused to close the switch 6, whereas the relay g has not yet run down. The two delayed-action relays are rendered currcntless by the opening of the contacts 21 and la whereupon the relay returns instantaneously into its zero position, whereas the relay g returns only gradually into its zero ositlon.

W en however, a disturbance such as an overload or a short circuit occurs in the network the switch I) which is provided with a maximum-opening device, opens again immediately after the closing and thus closes the contacts 2' and It, whereby the relays f and g are caused to begin to operate again. N ow the relay 7 must recommence its course from the very beginning, because it has returned into its zero position, whereas the relay g which has only moved back a very small extent, has on the contrar merely to finish the uncompleted remain er of its course. the relay f closes 9. am the switching-in circuit of the switch If the disturbance has not yet been removed, then the switch 6 will open again, and the o eration of the delayed action relay 1, which as moved back meanwhile begins for the third time, whereas the delayed action relay 9 continues its course.

After a total eriod of somewhat longer thanthirty secon the switch 5 will be closed for the third time in consequence of the relay f closing its contacts. If new the switch is opened again after the third closing, at this moment, that is to say, after thirty-five seconds, the delayedaction relay g has completed its course; it 0 one the contact a which interrupts the circuit of the auxiliary current supply h and renders all the relays d, f, g, as 7 well as the switching-in magnet m, currentless. The switch b now remains definitely open so long as the contact n is held open by means of the device 0., The contact 'n may be closed by operating the catch of the device 0.

If the switch I) does not open immediately after each closing, but remains closed for a certain period, the delayed-action relay g will in the meantime return into its zero position so that generally a definite switching ofl will take place solely in the case of a permanent overload or permanent short-cir cuit.

After the expiration of ten seconds In practice, the opening of the auxiliary i chit, aft-er the completion of the course a delayed action relay 9, is eflected by a ti relay which is caused to receive our it from the contact of the relay 9. The ontaet of this special relay can be closed n only by hand; in this case the hold up device 0 is dispensed with.

i 3 construction of the delayed-action re- L s is immaterial as regards the invention, but they must have the properties mentioned in the beginning hereof. 'lhey may be combined in one apparatus.

lVhat I claim is In a reclosing circuit breaker system, a cuit breaker having a tripping device opensaid circuit breaker in response to pre- 7 terimined line conditions, and automatic re e sing means comprising a reclosinf, coil for said circuit breaker, a first relay cevice actuated by the o ening of the circuit breaker energize sai reclosing coil for reclosing circuit breaker, and a second relay device nearing a member actuated by the opening of Y circuit breaker to more from an initial o iition to an end position where it de-encrgizaes itself and the circuit of said reclosing coil, the movement of said member being subtantially continuous and the time required bringing said member from its initial poion to its end period necessary r a single reclosure of the position being 'n times the circuit breaker, and means urging said memher to return from the intermediate positions thereof to its initial position at a speed that is slow compared to its movement toward the end osition.

2. In a rec osin r circuit breaker system, a circuit breaker aving a tripping device opening said circuit breaker in response to predetermined line conditions, and automatic reclosing means comprising a reclosin coil for said circuit breaker, a first relay evice actuated by the opening of the circuit breaker to energize said reclosing coil for reclosing the circuit breaker, and a second relay device having a member actuated by the opening ofsaid circuit breaker to move from an initial position to an end position where it de-energizes the circuit of said reclosing coil, the movement of said member being substantially continuous and the time required for bringing said member from its initial position to its end osition being 12 times the period necessary or a single reclosure of the circuit breaker, and means urging said memher to return from the intermediate positions thereof to its initial position at a speed that is slow compared to its movement toward the end position.

In testimony whereof I have signed my name to this specification.

FRITZ SCHMIDLIN. 

